The present invention relates to an instrument, and more particularly to an instrument for indicating an angular position of an object.
Bubble levels are generally known in form of transparent closed tubes partly filled with liquid so that a gas bubble is left in the tube. The reading of the bubble levels is not accurate.
U.S. Pat. No. 3,945,129 to Bergkvist discloses an instrument to indicate a more accurate angular position of an object. The line patterns of the instrument form a moire pattern to indicate the angular position of the object. The instrument can not tell an exact angular position of the object.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages of the conventional instrument for indicating an angular position of an object.